Electric-arc furnace.



N .880 338. v PATE TED FEB. 25 1908. 0 s. D. SPENGE. N

ELECTRIC ARC FURNACE. ABPLI OATIQH IILED 1330.17.1906.

4 SHEETS-SHEET 1.

an-ucnl'oz v flee ,diJenca,

QVi b1 cones No. 880,338. PATENTBD FEB. 25, 1908. S. D. SPBNOE.

ELECTRIC A BC FURNACE.

APPLICATION FILED DBO.17.1906.

4 SHEETSSHEET 4.

gnveufoz U Zan e r/flee Lgenca,

1% b1 zoom UNITED STATES PATENT OFFICE.

SIDNEY DEE SPENOE, OF OHATTANOOGA, TENNESSEE, ASSIGNOR OF ONE-FOURTH TO LEWIS SHEPHERD AND ONE-FOURTH TO DAVID L. SNODGRASS.

ELECTRIC-ARC FURNACE.

Specification of Letters Patent.

Patented Feb. 25, 1908.

To all whom it may concern:

Be it known that I, SIDNEY DEE SPENoE, a citizen of the United States, residing at Chattanooga, in the county of Hamilton and State of Tennessee, have invented certain new and useful Improvements in Electric- Arc Furnaces and I do declare the following to be a full,.clear, and'exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention is an improved electric arc furnace, and it consists in the construction, combination and arrangement of devices hereinafter describedand claimed.

One object of my invention is to provide improved means for shifting the electrodes in the body of the furnace, as may be required by the conditions of the work.

A further object is to provide improved means for varying the angles at which the side carbons are presented with reference to the intermediate carbons, and to also vary the length of the electric arcs formed between them.

A further object of my invention is to effect improvements in the construction of the furnace.

In the accompanying drawings, Figure 1 is a top plan view of an electric arc furnace, embodying my invention; Fig. 2 is a side elevation of the same; Fig. 3 is a vertical transverse sectional view of the same; Fig. 4 is an end elevation of the same; Fig. 5is a top plan view of a modified form of my invention; Fig. 6 is an elevation of the same; and Fig. 7 is a vertical transverse sectional view of the same.

The furnace 1 is here shown as of oblong rectangular form, open at its upper side, and having its side and end walls inwardlybeveled at their upper edges, as at 2. The said furnace is in practice made of fire brick, fire clay, or other suitable refractory material. In the side walls of the furnace, at suitable distances from the bottom thereof, are openings 3, which contract inwardly and receive the side carbons or electrodes 4. Reinforcing bands 5, 6 and 7, are shown extending around the furnace, disposed longitudinally thereof, and serving to strengthen the construction thereof. is removable and is in practice made of fire brick, iirc clay, or other suitable refractory material, in which are embedded longi- The top 8 of the furnace tudinallydisposed tie and reinforcing rods 9, the ends of which pass through bars 10 at the ends of the cover. Nuts 11 are screwed on the ends of the said rods and coact therewith to firmly secure the parts of the cover together. The said bars 10 are of inverted V-shape and their upper central portions are connected together by a longitudinallydisposed bar 12. Said bars 10 in effect form brackets which support the bar 12. The latter serves to support the inner carbons or electrodes 13, as hereinafter stated.

Braces 14 connect the longitudinal bar 12 with the bars or brackets 10. Said brackets and said bar 12 may be formed integral, as here shown. The inner electrodes 13 are made of carbon, and are of inverted T-shape in cross section. The said carbons are provided with removable carbon tips 15, by means of dowels 16, which project from the said tips and are cemented or otherwise suitably secured in openings in the carbons 13. The vertical webs or arms of the carbons 13 extend through openings 17 in the cover and their upper ends are secured in a channel bar 18, by means of suitable insulating cement or other material 19, as shown. The said channel bar 18 is supported by screws 20, 21, which operate in unthreaded openings in the bar 12 and have their 'lower ends swiveled to the channel bar 18,'as at 22. A nut 23 which bears on the bar 12 engages the screw 20 and is provided with a hand-wheel 24 and sprocket wheel 25. A nut 26 operates on the screw 21, bears on the bar 12, and is provided with a sprocket wheel 27. An endless sprocket chain 28 connects the sprocket wheels 25 and 27, and hence when the nut 23 is turned by the wheel 24 to move the screw 20 vertically in one direction, the nut 26 is turned simultaneously therewith to also operate the screw 21 and hence cause the channel bar 18 to be raised and lowered to raise and lower the inner carbons 13 in the furnace.

The bands 6, 7, of the furnace are connected together at the end walls of the furnace, by vertically-disposed bars 28, to which are secured the bearing studs or journals 29. Longitu(finally-extensible adjusting arms 30 have their inner ends pivotally mounted on the said studs or journals. Each of the said arms comprises an inner member 31 and on outer member 32, (lisposcd in overlapping relation and connected together by-bolts 33, which are carriedby the outer members 32 and operate in longi tudinal slots 34, with which the inner members 31 are provided. Said outer members 32 are formed with rack-teeth'35, on their lower sides, engaged by pinions 36 on an adjusting shaft 37, the said shaft being journaled in bearings 38, with which the inner members 31 are provided, said shaft bein further provided .at onev endwith a han -wheel 40, by means of which it may be readily turned to lengthensor shorten said arms 30, by causing the members 32 to move endwise on and with reference to the members 31. The said members 32 of the arms are connected by bars 41,w on which are mounted hplders'42 for the carbons 4, said holders having openings through which said together at the centers of the side walls of the furnace by pairs of vertically-disposed angle-bars 44. Adjusting arms 45, which are here shown as channeled, have their mner ends pivotally connected, as at 46, to the said bars 44. Their outer ends are supported by adjusting screws 47. Said screws operate in nuts 48, which are pivotally mounted in blocks 49 that are supported on the table or other object on which the furnace. is placed. The up er ends of said screws are swiveled to co ars 50, which are pivotally mounted in lugs 51, that are secured to and project from the outer ends of the bars or arms 45. Said bars or arms form supporting tracks for rollers 52, which are mounted at the lower ends of standards 53, which are secured to and depend from the bars 41. It will be understood that by raising and lowering the bars or arms 45, the arms 30 and bars 41 which constitute the side carbon-carrying elements will'be raised or lowered, to raise or lower the inner ends of the said side carbons, and keep them at the same level as the inner carbons 13.

A hook 54 and chain 55 are indicated in Fig. 2, for use in'raising and lowering the cover of the furnace, and hence also the inner carbons or. electrodes which are carried thereby. I

In the modified form of my invention, shown in'Figs..5, 6 and 7, the cover 56 is provided on its up er side with standard rackets 57, locate at the ends thereof. Said brackets are provided near their outer sides withhorizontally-dis osed slots 58. A fixed carbon holder 59 w ich supports carand the latter must be adjusted with ref-.

erence to the carbons 61. Adjusting screws '67 are rovided to effect such adjustment of the car ons 64. Said screws have their inner ends swiveled to blocks 68, which are screwed on the carbon holder 59. The adjustable carbon holders 63 have nuts 69 secured thereon, which are engaged by the said adjusting screws. The latter are provided with hand-wheels 70 at their outer ends 'to enable them to be readily turned, and are caused to turn in unison by sprocket wheels 71 and endless sprocket chains 72, as shown. From the foregoing description, taken in connection with the accompanying drawings, the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion, and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of this invention, as defined by the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is,

1. An electric arc furnace having a removable cover provided with openings, a fixed supporting element over said 0 enings, a movable supporting bar, electro es carried by said su porting bar and extending through sai openings, screws connecting said supporting bar and the fixed supporting element, and connections between said screws to cause the same to turn in unison, for the purpose set forth.

2. An electric arc furnace having a removable cover, longitudinall disposed tie and reinforcing rods extending through. said cover, upwardly extending brackets at the ends of the cover and to which the ends of the said rods are attached, a fixed supporting element connecting the said brackets and disposed above thecover, a movable bar, means connecting said supporting element and said supporting bar, and screws to adjust the latter, and electrodes carried by and.

adjustable with said su porting bar.

3. An electric arc Furnace having vertically adjustable inner electrodes, side electrodes, pivotally mounted longitudinally adustable arms carrying said side electrodes and means to raise and lower said arms and hence also said side electrodes.

4. An electric arc furnace having vertically adjustable inner electrodes, side elec- 5 trodes, pivotally mounted longitudinally adjustable arms carrying said s1de electrodes, means to adjust said arms'longitudinally, to. correspondingly adjust said side'electrodes, a pivotally mounted supporting element for 10 sald adjustable arms, and means to vertically adjust said supporting element, for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

SIDNEY DEE SPENCE.

Witnesses:

T. Porn SHEPHERD, FRED S. SHEPHERD 

